Pumping apparatus



Nov' 4, N``vf PUMPING APPARATUS SMITH 2 vsheets-sheet 1 Filed Oct. 13. 1955 Nov. 4, 1958 N. v. SMITHl 2,853,767

PUMPING APPARATUS 2 Sheets-Sheet 2 Filed Oct. 13. 1955 INVENToR. JVZ'M I( .SM/r# United States Patent' PUMPING APPARATUS Neil V. Smith, Los Angeles, Calif.

Application Uetober 13, 1955, Serial No. 540,225

12 Claims. (Cl. 10S-49) This invention relates to a pumping apparatus and is particularly concerned with a structure for delivering uid under pressure and in volume when there is a demand for the fluid to be supplied, a general object of the invention being to provide a simple elfective pumping apparatus that is economical to operate and which is reliable.

The apparatus of the present invention is particularly useful' in connection with the delivery of hydraulic fluid or liquid which is ordinarily delivered by some type of continuously operated pump. Such pumps are usually motor driven and employ bypass or pressure relief valves and also accumulators. The bypass valve diverts the liquid that is not required while the accumulator supplies liquid when there is a large demand for it. The bypassing of fluid, for example through an orifice, results in generation of heat and requires the use of coolers and often results ink breakdown of the desirable physical qualities of the liquid being handled. Also, such pumps pulsate in that they do not deliver an absolutely steady stream of liquid. Further,the pumps under consideration are usually motor driven requiring the input of power even when there is no 'demand for the liquid', and are characterized by close iitting,v precision made parts that have sliding engagement with each other.

it is an object of this invention to'provide a pumping apparatus that supplies or delivers uid under a head of pressure whereby fluid is delivered to a line under static pressure without the use of power, and wherein power is used only when the iluid is allowed to be delivered from the apparatus to 'ow through the line.

An object of this invention is to provide a pumping apparatus that, when in operation, delivers fluid under pressure at any time on demand and at any required volume and that delivers a smooth continuous stream of fluid without the use of an accumulator.

It is still another object of this invention to provide a pumping apparatus characterized by two like units and which eliminates the use of any mechanical or electrical control connections between the units. By providing fluid connections between the units and fluid controlled valves, the two units that applicant has provided alternately operate to deliver a steady ow of fluid.

it is still another object ofl this invention to provide an apparatus of the character above referred to that has a control that synchronizes operation of the two units involved whereby a continuous nonpulsating llow of fluid is delivered from the apparatus. l

lt is still another object of this invention to provide an apparatus of the character referred to wherein the delivery pressure of uid is easily and quickly varied with a minimum amount of effort.

It is still another object of this invention to provide a pumping apparatus of the character above referred to wherein there is movement of parts and of fluid only when uid is delivered from the apparatus to meet a demand and wherein practically no heat is generated in the process of handling and deliveringsaid uid.

2,858,767 K APatented Nov. 4, 1958I 2 The various objects and features of my invention will be fully understood from the following detailed descrip-v tion of typical preferred forms and applications of my invention, throughout which description reference is made t-o the accompanying drawings, in which:

Fig. 1 is an elevation of the apparatus that I have provided, portions thereof shown in section. FigfZ is an enlargedk detailedl sectional view of one of the valves `at the upper end of the structure and taken as indicated by line 2-2 on Fig. l. Figs. 3 and 4 are diagrammatic views illustrating typical conditions of the apparatus duri ing the operation thereof, andFig. 5 is a sectional yview of a portion of the structure illustrating a modified form of the invention.

The pumping apparatus that I have providedis particularly adapted to deliverfa liquid such as oil and is particularly adapted to be driven by air under pressure. l have, therefore, shown my invention in this connection in which ycase there are two like pumping units X and Y that receive liquid from .a reservoir Z and deliver it under pressure to a supply line P. A return line Pf is shown connected to the reservoir to repleinsh the supply` of liquid therein. The pumping units X and Y are driven pneumatically by air delivered through an air supply pipe or pipes L from'a suitable compressed air supply (not shown), which pipe L is under control of a variable pressure regulator valve R. lt will be readily understood that any' suitable air supply maybe employed and that the regulator valve R is employed to control the amount of air pressure used to operate the units X and Y.

The pump units X and Y are preferably cylinder and piston units and as sh-own are like units each comprising generally, a pump barrel A, a pump ram B operable in the barrel A, a piston C carried by the ram B and slidably engaged in the barrel A, an inlet valve D carried by the barrel A, a transfer valve E preferably carried bythe piston C, a drive cylinder F concentric with and projecting from the barrel A, a drive piston G operating the ram B and slidably carried in the cylinder F, and a control means H coupling the units X and Y so that they are operated alternately relative to each other. It is to be understood that the construction of the units X and Y may be varied, for example, they may be diaphragm type units in place of the particular cylinder and piston units herein disclosed. A manifold M is provided to carry the pumping units X and Y, preferably in side by side relationship and to interconnect the delivery ends of the barrels A of the two units so that they are in communica tion with the supply line `P to deliver liquid from the' apparatus when there is a demand therefor.

`The pump barrel A is a tubular part having a sub-I stantially thick cylinder Wall 10 adapted to withstand relatively high pressure. In practice, the barrel A is vertically disposed and is immersed in the liquid carried in the reservoir Z. vAs4 shown, the manifold M is an elongate horizontally disposed` part supported by the upper portion o-f the reservoir Z and it has a pairof recesses 11 and 11 each for receiving the upper end portion of a pump barrel A. A suitable O-ring seal is shown carried in an annular 'groove in the manifold M and engaged with the wall 10 of the barrel A.` The recesses are in full communication lwith the interiors o f the barrels A and are interconnected by a passage 13 and are in communication with the line P so that both the'units X and Y deliver fluid directly into the line P.

A barrel head 14 is shown at theV lower end of the v barrel A to close the said end of the barrel and is secured thereto by suitable tie rods 15 lthat extend upwardly to the manifold yM. The rods 15v are threaded into the manifold M and extend'through openings in the head 4V14 f Where nuts `-16 are employed to secure the parts together in clamped engagement. A suitable O-ring seal is shown carried in an annular groove in the head 14 to seal with the wall of the barrel A.

'The manifold M, in the form of the invention illustrated, forms barrel heads 17 at the upper ends of the barrels, one for each barrel, to close the said ends of the barrels and to pass the rams B hereinafter described. As shown, the ram B is one-half the area of the barrel A and an opening 18 one-half the area of the inner diameter kof the barrel A extends through the manifold M on an axis'concentric with the axis of the barrel A to slidably pass the ram. A suitable O-ring seal is shown carried in an annular groove in the manifold M to have sliding sealing engagement with the exterior of the ram B.

The pump ram B is provided to displace liquid from the interior of the barrel' A and is a straight elongate cylindrical part that slidably passes through the opening `18 in the manifold M to enter the barrel A from the upper end thereof. The ram B has a smooth exterior wall 19 that has sliding engagement with the seal at the opening 18 and when the ram B advances into the barrel A, an amount of liquid is displaced from the barrel equal to the volumetric displacement of the portion of the ram that enters into the barrel A. Conversely, when the ram B is retracted from the barrel A, liquid fills the space previously occupied by the ram B.

The pump piston C is provided to separate the interior of the barrel A into the upper and lower chambers 20 and 21 and to lift liquid in the barrel A when the ram B is moved upwardly relative to the'barrel. As shown, the piston C is a simple disc-shaped part carried at the lower end of the ram B where it is held in engagement with a lower end face 22 on the ram by means of a nut or bolt 23. The piston C has a smooth cylindrical exterior wall 25 that has sliding engagement with the interior of the wall 10 of barrel A and a suitable 0-ring seal is shown carried in an annular groove in the piston C to engage with the interior of the wall 10. When the ram B is shifted in the barrel A, the piston C is likewise moved to alternately vary the volumetric displacement of the chambers 20 and 21.

The inlet valve D is provided to admit liquid into the barrel A at the lower end thereof and is, therefore, preferably located at or incorporated in the barrel head 14. 'I'he valve D is in the nature of a check valve that allows flow from the reservoir into the lower chamber 21 of the barrel A that stops flow out of the chamber 21. The

valve D may be of any suitable construction and is preferably a disc-shaped valve having a flat sealing face 26 that has flat engagement with a flat seat 27 provided on the upper side of the head 14 within the chamber 21. In practice, a stem 28 depends from the valve D to extend through the head 14 and a spring normally yieldingly urges the stem 28 downwardly so that the face 26 has sealing engagement with the seat 27. As shown, ports 29 extend through the head 14 to open at the seat 27 where they'are opened and closed by vertical movement of the valve D. When the ram B and piston C are operated in a manner to draw liquid into the chamber 21, the valve D opens to pass liquid through the head 14.

The transfer valve E is provided to pass liquid from the chamber 21 to the chamber 20 and is, therefore, preferably located at or incorporated in the pump piston C that separates the two chambers. The valve E is in the nature of a check valve that allows flow from the chamber 21 into the chamber 20 of the barrel A and that stops ow out of the chamber 20. The valve E may be of any suitable construction and is preferably a disc type valvehaving a flat sealing face 30 that has at engagement with a flat seat 31 provided on the upper side of the piston C within the chamber 20. In practice, the valve E is carried in an annular channel formed by a turned portion 32 at the lower end of the ram B in which case an opening is provided in the valve E to freely pass the turned porition 32.. A spring 33 .nor-

mally yieldingly urges the valve E downwardly so that the face 30 has flat sealinglengagement with the seat 31. As shown, ports 34 extend through the piston C to open at the seat 31 where they are opened and closed by vertical movement of the valve E. When the ram B and piston C are operated in a manner to transfer liquid from the chamber 21 into the chamber 20, the valve E operates to pass liquid through the piston C. l

The elements thus far described form a pump for moving fluids such as oil or the like. When the pump ram B and piston C are lifted or moved upwardly, the liquid C is drawn into the chamber 21 through the valve D while the liquid is delivered from the chamber 20 by movement of the piston C. `It will be observed that the volume of liquid entering the chamber 21 is twice that of the volume of liquid delivered from the chamber 20 due to the displacement of the ram B. When the pump ram B and piston C are lowered or moved downwardly, the liquid in the chamber 21 is transferred to the chamber 20, half of the liquid being delivered from the chamber 20 to the manifold M due to the displacement of the ram B. Thus, the pump that I have provided is double acting and delivers an equal volume of liquid on both upward and downward shifting of the ram B and piston C.

In the form of the invention illustrated, where the units X and Y are cylinder and piston type units, I have provided like motors each formed by a drive cylinder F and a piston G above referred to. The motor formed by the cylinder F and piston G is provided to operate or shift the ram B and piston C so that they are reciprocated upwardly and downwardly in the barrel A to the end that the pump portion of the structure operates to deliver fluid as above described. In accordance with the invention, the motor structure of each unit X or Y is in alignment with the pump structure to be driven thereby in which case, the drive cylinder F is carried on an axis concentric with the central vertical axis of the barrel A. The drive cylinder F is substantially larger in diameter than the barrel A so that the force developed in the motor structure is multiplied when applied to the ram B and piston C due to the differential in effective area of the motor structure and pump structure.

The drive cylinder F involves a cylinder wall 35 and upper and lower cylinder heads 36 and 37. The wall 35 has a smooth interior for receiving the drive piston G and the heads 36 and 37 close the ends of the wall 35. The cylinder heads 36 and 37 are secured to the wall 35 by suitable rods 38 that extend from the manifold M and through openings in the heads. The tie rods 3S are threaded into the manifold and extend through the heads, there being nuts 39 at the upper head 36 that secure the parts together in .clamped engagement. The lower head 37 has a at face engaged with the flat top of the manifold M to the end that the cylinder F projects vertically from the manifold in alignment with the barrel A and parts related thereto.

The drive piston G is provided to operate the ram B and piston C and is a double `acting piston operable in the cylinder F. The piston G is a circular part carried on the upper end of the ram B and involves a body 40 and oppositely faced upper and lower sealing lips 41 and 42. The body 40 is an elongate member, the lips 41 and 42 being carried at the upper and lower end faces 43 and 44 thereof. A central opening extends through the body 40 to pass a ystud 45 that projects up from the upper end of the ram B and a nut 46 is threaded onto the stud 45 to retain the body 40 onthe upper end of the ram. In practice, retaining plates 47 and 48 retain the lips 41 and 42 in operating position on the body 40. The lips are cup shaped and are disposed to face oppositely or away from each other, as shown.

The control means H that I have provided to couple the units X and Y controls the said units so that they are synchronized and reciprocated independently and alternately relative to each other to the end that a steady nonpulsating flow of liquid is delivered to the manifold M. The control means H is provided to direct the flow of air from the pipe line L to the ends of the cylinders F of the two units X and Y. In accordance with the invention, the means H involves a control valve 50 for the drive cylinder F of the unit X, a control valve 5l for the drive cylinder F of the unit Y, upper and lower ports 52 and 53 in the wall 35 of the cylinder F of the unit X, upper and lower ports 54 and 55 in the wall 35 of the cylinder F of unit Y and flow lines connecting the said ports to the valves 50 and S1 as hereinafter described.

The control valves 5) .and 51 are alike and may be any suitable four-way pilot operated valves. That is, the valves are such that when in one position, air is admitted to the upper end of a cylinder F and is exhausted from the lower end thereof and are such that when in another position, air is admitted to the lower end of a cylinder F and is exhausted from the upper end thereof. Such a valve is illustrated in Fig. 2 of the drawings and involves a chest 5,7, a slide 58 operable in the chest, and a piston 59. Air under pressure from the pipe L is directed into a chamber in the valve chest while the slide 58 is operable in the said chamber to alternately cover and uncover ports 61 and 62, the port 61 being in communication with the upper end of the cylinder F through a passage 61', the port 62 being in communication with the lower end of the cylinder F through a passage 62. The slide 58 is also operable to alternately cover and uncover exhaust ports 60 so that the ports 61 and 62 are alternately in communication with the ports 6i). The piston 59 is operable in a cylindrical opening 63 and is a spool shaped part that engages with a projection on theslide 58. The cylinder opening 63 extends between the front and rear of the valve and the ow lines above referred to are connected with the front and rear of the opening 63 to shift the piston 59 in the opening and to shift the slide 58. It will be apparent that operation of the two valves between the positions indicated will result in reversing the direction of movement of the drive pistons G in the cylinders F.

In order to gain the desired synchronized control and alternate operation of the units X and Y, the ow lines of the control means are connected to the ports and valves as follows: The upper port 52 of unit X is in communication with the front of the cylinder 63 in valve 51 on the unit Y through a line 70, while the lower port 53 is in communication with the rear thereof through a line 71 (Fig. 3). The upper port 54 of unit Y isl in communication with the rear end of the cylinder opening 63 in the valve 50 on unit X through a line 72, while the lower port 55 is in communication with the front thereof through a line 73 (Fig. 4). The ports S2, 53, 54, and 55 are positioned to be opened and closed by movement of the piston G when the piston G is about midway intermediate the upper and lower ends of the cylinder F. Further, the upper ports 52 and 54 are so related to the pistons G that they are opened and closed only by the upper lips 41 thereof, while the lower ports 53 and 55 are so related to the piston G that `they are opened and closed only by the lower lips 42v thereof. Thus, when the upper ports 52. or 54 are opened, air pressure from the upper portions of the cylinders is delivered to the control valves, and when the lower ports 53 or 55 are open, air pressure from the lower portions of the cylinders F is delivered to the control valves. It will be apparent that ports in one unit control the position of the valve at the other unit to the' end that the direction of movement of the pistons G is determined.

In accordance with the invention, in order to deliver the same driving force to the ram B regardless of whether the ram is moving upwardly or downwardly, the parts of the apparatus are proportioned as follows: The effective area of the ram B is to the effective area of the drive piston G, as the annular area surrounding the ram inthe barrel A is to the annular area surrounding the ram in the cylinder F. With this-relationship of parts, the pressure of liquid displaced from the annular area surrounding the ram in the barrel A is the same regardless of the direction in which the ram is moving.

In Fig. 5 of the drawings, I have illustrated a modified form of the invention wherein heat transfer means K is provided to prevent frosting of the valves 50 and 51 and to cool the lluid delivered by the pumping apparatus. There is a tendency, under some conditions, for the valves to freeze or frost-up and also for the temperature of the fluid being handled to rise. For example, when rapid operation of the apparatus occurs, there is a substantial amount of expansion of air which air is eX- hausted through the valves 50 and 51 vand with considerable cooling effect. If moisture is present, the valve action is likely to be affected. Further, when rapid operation of the apparatus occurs, there is likely to be some heating of the fluid handled. Therefore, the heat transfer means K that I have provided acts to absorb heat from the fluid handled in order to prevent freezing of the valves 50 and 51.

As clearly shown in Fig. 5 of the drawings, the means K involves the pressure supply line P which is provided with a return line P that directs ow of uid from the manifold M to the upper end of the apparatus where the valves 50 and 51 occur. As above described, the cylinder heads 36 carry the valves 50 and 51 in which case I prefer to incorporate the means K in the heads 36. As shown, the heads may be made integral with each other to form a multiple cylinder head 36 that is jacketed by providing suitable chambers 80. The chambers are in communication with each other and with an inlet 81 and an outlet 82, the inlet 81 being connected with the return line P. The outlet 82 is connected with a delivery or pressure supply line P. It will be apparent that uid delivered by the apparatus passes through the head 36. Since the valve chests 57 are mounted directly onto the head 36 (see Fig. 2) heat transfer occurs directly between these parts with the result that freezing of the valves is eliminated.

From the foregoing, it will be apparent that only a few simple, easily made parts and elements are required in order to construct the pumping apparatus that I have provided. In carrying out the invention, the pressure regulating valve R may be easily adjusted to the desired pressure whereupon the apparatus is immediately in operation. However, there is no flow of air unless there is a demand for liquid from the manifold M and then only a flow in proportion to the amount of liquid delivered. Assuming that both pistons G are centered and that they drift downwardly or move by demand yand that the upper ports 52 and 54 are uncovered simultaneously, the cylinders F of both units X and Y are pressurized from opposite ends. After the latter operation, normal operation continues, wherein one unit works at a time followed by working of the other unit and so on. That is, there are four separate reciprocating movements involved in one complete working cycle of the apparatus. Since both units X and Y are in continuous pressure communication with each other through the manifold M and since both units are of identical construction, one of the units will obviously start its working stroke due to less friction in its construction as compared with the other unit, and said other unit will remain motionless until the end of the work stroke of the rst mentioned unit whereupon it will begin its work stroke.

Typical work strokes of the apparatus are illustrated in Figs. 3 and 4 of the drawings. In Fig. 3 the port 52 (see Fig. l) is opened and valve 51 is pressurized through line 70 so that the piston G of unit Y moves downwardly, and the port 55 (see Fig. 1) is opened and valve 50 is pressurized through line 73 so that the piston G of unit X moves upwardly. In Fig. 4 the port 52 remains opened to the end that the piston G of unit Y 7 Y continues to move downwardly, and the port 54 (see Fig. l) is opened and valve S is pressurized through line 72 so that the piston G of unit X will move upwardly. It will be understood that opening of port 53 (see Fig. 1') will pressurize the valve 51 through line 71 to the end that the piston G of unit Y is moved upwardly.

When the apparatus is in operation, any appreciable pressure load will prevent delivery from more than one pump at a time. The other pump, however, is pressurized and ready to take up delivery at full pressure the instant the first pump reaches its stroke end. This results in a fluid or air operated pump that can be installed on the line and which requires no electric motors or relief valves, has no springs or any mechanical controlling mechanisms whatsoever and uses no power except on demand.

Having described only typical preferred forms and applications of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any Variations or modifications that may appear to those skilled in the art and fall within the scope of the following claim.

Having described my invention, I claim:

l. A pumping apparatus of the character described, including, an elongate pump barrel, a head closing one end of the barrel, the other end of the barrel being in open communication with a delivery line, a valve admitting fluid to the head end of the barrel, a ram entering the barrel at said other end and movable longitudinally relative thereto, said ram being one-half the effective area of the effective area of the barrel, a piston at the end of the ram and slidably engaged in the barrel, and a valve allowing uid to pass the piston to be delivered from the head end of the barrel to the said other end thereof, whereby equal amount of fluid is delivered from said line upon reciprocation of the ram in either direction.

2. A pumping apparatus of the character described, including, an elongate pump barrel, a head closing one end of the barrel, the other end of the barrel being in open communication with a delivery line, a valve at the head and admitting fluid to the barrel, a ram entering the barrel at said other end and movable longitudinally relative thereto, said ram being one-half the effective area of the effective area of the barrel, a piston at the end of the ram and slidably engaged in the barrel, a valve allowing uid to pass the piston to be delivered from the head end of the barrel to the said other end thereof, a drive cylinder fixed to and projecting from said other end of the barrel and closed at its ends by cylinder heads, the cylinder head adjacent the barrel slidably` passing the ram so that it enters said cylinder, a drive piston at the end of the ram and slidably engaged in the cylinder, and a control valve alternately admitting and exhausting fluid under pressure to opposite ends of the cylinder to reciprocate the drive piston therein, whereby equal amount of fluid is delivered from said line upon reciprocation of the ram in either direction.

3. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting fluid to the barrels, a ram entering each barrel at said other end thereof and movable longitudinally relative thereto, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a valve allowing fluid to pass the pistons to be delivered from the head ends of the barrels to said other ends thereof, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control valve alternately admitting and exhausting fiuid under pressure to opposite ends of each cylinder to reciprocate the drive pistons therein, whereby a continuous flow of fluid is delivered from said lines upon reciprocation of the rams in either direction.

' 4. A pumping apparatus of the character described, including, a manifold having a pair of recesses in fluid communication with each other and in communication with a delivery line, a pair of elongate pump barrels carried by the manifold and one at each recess, and a head closing one end of each barrel, the other end of each barrel being open to the manifold, a valve at each barrel head and admitting fluid to the barrels, a ram entering each barrel at said other end through an opening in the manifold and movable longitudinally relative thereto, each ram being one-half the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a Valve at each piston and allowing fluid to pass the pistons to be delivered to the manifold, a pair of drive cylinders xed to and projecting from the manifold, one at each recess, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the manifold slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control valve alternately admitting and exhausting fluid under pressure to opposite ends of each cylinder to reciprocate the drive pistons therein, whereby a continuons ow of fluid is delivered from the manifold to said line upon reciprocation of the rams in either direction.

5. A pumping apparatus of the character'described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admiting fluid to lthe barrels, -a ram entering each barrel at said other end thereof and movable longitudinally relative thereto, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, -a valve at each piston and allowing fluid to pass the pistons to be delivered from the head ends of the barrels to said other ends thereof, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slid-ably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each rarn and slidably engaged in the cylinders respectively, and a control means for synchronizing operation of the pair of rams so that they reciprocate independently and alternately relative to each other, including, a pair of control valves, one for each cylinder and each having a shiftable element alternately admitting and exhausting fluid under pressure to opposite ends of the cylinder, and control connections from one cylinder to the valve controlling the other cylinder whereby said valves are responsive to the position of the drive pistons in the cylinders, whereby a continuous flow of fluid is delivered from said line upon reciproc-ation of the rams in either direction.

` 6. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting fluid to the barrels, a ram entering each barrel at said other end thereof and movable longitudinally relative thereto, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a valve at each piston and allowing fluid to pass the pistons to be delivered from the headl ends of the barrels' to said other ends thereof, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control means for synchronizing operation of the pair of rams so that they reciprocate independently and alternately relative to each other, including,` a` pair of control valves, one for each cylinder and each having a shift-able element alternately admitting and exhausting fluid under pressure to opposite ends of the cylinder, ports in the walls of the cylinders and opened and closed by movement of the drive pistons in said cylinders, and control connections from said ports of one cylinder to the valve controlling the other cylinder, whereby a continuous tiow of lluid is delivered from said line upon reciprocation of the rams in either direction.

7. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing oneA endV of each barrel, the other end of each barrel being in# open communication with each other and with a` delivery line, a valve at each 'barrel head and admitting liuid to the barrels, a ram entering each barrel at said other end thereof and movable longitudinally relative thereto, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the 4barrels respectively, a valve at each piston and allowing fluid to pass the pistons to be delivered from the head ends of the barrels to sai-d other ends thereof, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control means for synchronizing operation of the pair of rams so that they reciprocate independently and alternately relative to each other, including, a pair of control valves, one for each cylinder and each having a shiftable element alternately admitting and exhausting fluid under pressure to opposite ends of the cylinder, upper and lower ports in the walls of the cylinders and opened and closed by movement of the drive pistons in said cylinders, and control connections from said ports to the valves controlling the cylinders, whereby a continuous flow of fluid isdelivered from said line upon reciprocation of the rams in either direction.

8. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting fluid to the barrels, a ram entering each barrel at said other end thereof and movable longitudinally relative thereto, each ram being one half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a valve at each piston and allowing uid to pass the pistons to be delivered from the head end of the barrel to said other end thereof, a pair -of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control means for synchronizing operation of the pair of rams so that they reciprocate independently and alternately relative to each other, including, a pair of control valves, one for each cylinder and each having a shiftable element alternately admitting and exhausting fluid under pressure to opposite-ends of the cylinder, upper and lower ports in the walls of the cylinders, said upper ports posi= tioned to benopened by downward movementof the drive pistons in said cylinders, said lower ports positioned to be opened by upward movement of the drive pistons in said cylinders, and control connections from said ports of one cylinder to the valve controlling the other cylinder, whereby a continuous flow of fluid is delivered from said line upon reciprocation of the rams in either direction.

9. A pumping apparatus of the character described', including7 .a pair of elongate pump barrels, a head closing one end' of each barrel, the other endof each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting uid to the barrels, a ram entering each barrel at said other end' thereof and movable longitudinally relative thereto, each ram being one-half the effective area of the effective area of the barrel, a. piston at the end of each ram and slidably engaged in the barrels respectively, a valve at each piston4 and allowing liuid to pass the pistons to be derlivered from the head end of the barrel to said other end thereof, a pair of drive cylinders fixed to and projecting from said' other ends o f the barrels respectively, one at each barrel, and closed at thev ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, and a control means for synchronizing operation of the pair of rams so that they reciprocate independently and alternately relative to each other, including, a pair of control valves, one for each cylinder and each having a shiftable element alternately admitting and exhausting iiuid under pressure to opposite ends of the cylinder, upper and lower ports in the walls of the cylinders, said upper ports positioned to be opened by downward movement of the drive pistons in said cylinders, said lower ports positioned to be opened by upward movement of the drive pistons in said cylinder, control connections from the upper ports to one end of the valve controlling the other cylinder, and control connections from the lower ports to the other end of the valves controlling the other cylinder, whereby the Valve elements are shifted to cause reciprocation of the rams in one direction and then the other and whereby continuous flow of liuid is delivered from said line upon reciprocation of the rams in either direction.

l0. A pumping apparatus of the character described, including, an elongate pump barrel, a head closing one end of the barrel, the other end of the barrel being in open communication with a delivery line, a valve at the head and admitting fluid to the barrel, a ram entering the barrel at said other end and movable longitudinally relative thereto, said ram being one-half the effective area of the effective area of the barrel, a piston at the end of the ram and slidably engaged in the barrel, and a valve at the piston and admitting fluid to pass the piston to be delivered from the head end of the barrel to said other end thereof, whereby equal amount of liuid is delivered from said line upon reciprocation of the ram in either direction, the effective area of the ram being to the effective area of the drive piston as the annular area surrounding the ram is to the annular area surrounding the ram in the cylinder.

11. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting fluid tothe barrels, a ram entering each barrel at said other end thereof and movable longitudinally relative to the barrel, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a valve allowing uid to pass the pistons to be delivered from` the head end of each barrel to said other end of each barrel, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, on'e at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing to rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, a control valve alternately admitting and exhausting fluid under pressure to opposite ends of each cylinder to reciprocate the drive pistons therein, and heat transfer means at the control valve, said delivery line passing fluid through said means, whereby a continuous ow of iuid is delivered from said lines upon reciprocation of the rams in either direction.

12. A pumping apparatus of the character described, including, a pair of elongate pump barrels, a head closing one end of each barrel, the other end of each barrel being in open communication with each other and with a delivery line, a valve at each barrel head and admitting fluid to the barrels, a ram entering each barrel at said other' end thereof and movable longitudinally relative to the barrel, each ram being one-half the effective area of the effective area of the barrel, a piston at the end of each ram and slidably engaged in the barrels respectively, a valve allowing iluid to pass the pistons to be delivered from the head ends of the barrels to Said other ends of the barrels, a pair of drive cylinders fixed to and projecting from said other ends of the barrels respectively, one at each barrel, and closed at the ends thereof by cylinder heads, the cylinder heads adjacent the barrels slidably passing the rams so that the rams enter the said cylinders, a drive piston at the end of each ram and slidably engaged in the cylinders respectively, a control valve alternately admitting and exhausting uid under pressure to opposite ends of each cylinder to reciprocate the drive pistons therein, and heat transfer means at the control valve including said cylinder heads having fluid handling chambers therein, said delivery line passing uid through the said chambers, whereby a continuous ow of fluid is delivered from said lines upon reciprocation of the rarns in either direction.

References Cited in the le of this patent UNITED STATES PATENTS 2,442,916 Buchanan June 8, 1948 2,579,670 Hjarpe Dec. 25, 1951 2,660,955 Kent et al Dec. 1, 1953 

